# 民法 / Civil Code — 第百四十三条 (Article 143)

- Law: 民法 (Civil Code), 明治二十九年法律第八十九号
- English title "Civil Code": Ministry of Justice translation
- Kind: Act — the distinction between 法律 (Act), 政令 (Cabinet Order), 省令 (Ministerial Order) and 条例 (local ordinance) decides who may issue it and what it may say.
- Provision: 第百四十三条 (Article 143)（暦による期間の計算） — address `art-143`
- Text in force since: 2026-06-24
- URL (the page that opens at this provision): https://japanlaw.org/en/civil-code/art-143
- Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/129AC0000000089/art-143
- Every provision below carries its address and both URLs on the line under it.
- Japanese text: e-Gov 法令検索, Digital Agency (デジタル庁). English: as marked on each line below.

Only the Japanese as published by the government has legal effect; the text
below is a copy of it. Every English rendering below is a translation and
says which kind: the Ministry of Justice's translation, or this
site's machine translation, whose model and date the Sources list names.
They are never merged and never substituted for one another.

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### 第百四十三条（暦による期間の計算） — (Computation of Period with Reference to Calendar)
<sup>caption: Ministry of Justice translation — Japanese Law Translation Database System</sup>
<sup>art-143 · https://japanlaw.org/en/civil-code/art-143 · https://japanlaw.org/l/129AC0000000089/art-143</sup>

  **第一項**  週、月又は年によって期間を定めたときは、その期間は、暦に従って計算する。
  <sup>art-143/par-1 · https://japanlaw.org/en/civil-code/art-143/par-1 · https://japanlaw.org/l/129AC0000000089/art-143/par-1</sup>
  If a period is provided for in weeks, months, or years, the period is calculated in accordance to the calendar.
  <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

  **第二項**  週、月又は年の初めから期間を起算しないときは、その期間は、最後の週、月又は年においてその起算日に応当する日の前日に満了する。ただし、月又は年によって期間を定めた場合において、最後の月に応当する日がないときは、その月の末日に満了する。
  <sup>art-143/par-2 · https://japanlaw.org/en/civil-code/art-143/par-2 · https://japanlaw.org/l/129AC0000000089/art-143/par-2</sup>
  If a period does not commence at the beginning of the week, month, or year, that period expires on the day immediately preceding the day which corresponds to the commencement day in the last week, month or year; provided, however, that if the period is provided for in months or years and the last month does not contain a corresponding day, the period expires on the last day of that month.
  <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

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## Sources

- e-Gov 法令検索, Digital Agency (デジタル庁) — 民法 — the text in force from 2026-06-24 (https://laws.e-gov.go.jp/law/129AC0000000089/20260624_508AC0000000045), retrieved 2026-10-11
- Japanese Law Translation Database System, Ministry of Justice (法務省) — Civil Code — Ministry of Justice translation (part 1 of 2) (https://www.japaneselawtranslation.go.jp/en/laws/view/4848/tb), retrieved 2026-10-11
- This site's parser, version 190 — 民法 — structure, counts, cross-references and defined terms, computed 2026-10-11